Continuous distillation of oils



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' 1,6133 4 Jan n 1927' F. A. HowARD Er AL s CONTINUOUS -DISTILLATCN OFOILS Filed June 15, 1922 Patented Jan. 11, 1927.

UNITED STATES- PATENT oFHcE. y

FRANK A. HOWARD AND NATHANIEL E. LOOMIS,'OF ELIZABETH, NEW JERSEY, AS-SIGNOBS TO STANDARD DEVELOPMENT COMPANY, A CORPORATION OF DELAWARE.

CONTINUOUS msrrLLA'rIoN or oILs.-

Applicatlon led June 15,

y The present invention relates to the distillation of hydrocarbon oils,and more particularly to the continuous distillation or reduct-ion of:oil in the presence of steam. It will be fully understood from thefollowing description, illustrated bythe accompanying drawing, in which-Figure 1 shows diagrammatically and in plan an arrangement of stillssuitable for use 1n in connection with the resent invention;

Fig. 2 shows, alsov iagrammatically, in pd elevation the arrangement ofstills of ig. 1 Fig. 3 is a broken horizontal sectionV through one ofthe stills' used in connection with the resent invention and j Fig. 4 sows a vertical section through one ofthe stills employed in connectionwith the present invention on the line 4 of Fig. .3.

Referring-'more particularly to the drawings, the numerals 11, 12,13, 14and 15 in- `dicate successive stills on-.a .continuous battery otstills, each provided witha suitable` tired setting, as'in cateddiagrammatically at 50'in Fig. 2. yThese stills may be of any suitableconstruction and are indicated as gbeingjof' the horizontal,cylindricaltype.

They may be set. at successively 'lower levels in the manner usual inthe art tojprovide as :w farv as possible lfor a gravity -flow of oilthrough the several stills. .As the setting of the stills is nota partof the present invention, it is not indicated in the drawings. y

-The oil to be distilled, which'maysutably. be, for example',`aPennsylvania or midvcontinent, crude, may, if desired, be initiallypreheated' and is 'fed from line 16 into valved line 17 enteringstillll. Residue from still 11 passes out through '-valvedline 18 into:line

.40 19, from which valved line 20'leads into-still` v12. Similarly,-residuepa'sses from still 12 throu h v alved ,linej5I-21 and; line 22into valve line`23 leading into still 13.1 From still 13 residue passesthrough valved line 24 and line 25 into valved line 26 leading intostill 14.'- From still 14 residue passes throughv valved line 27 andline 28 into yalved line 29 Vleading' into still-15. From still .15 thetar or residue passes through valved line30 into 5 line 31, 'which malead to a suitable tar cooler (not shown Valved by-pas'ses 32 areprovided for vby-passing any one of the 1922. vserial No. 568,457.

section, respectively. The indirect heat exchanger may suitably be ofthe tubular type. In the embodiment'shown the tubes 35 are curved inU-shape, and terminate inheaders 36 and 37, respectively. A vapor line38 passes through .the wall of the still and opens into the header 36.Vapor line 39 likewise passes through thewall of the still and opensinto header 37. Each of the stills 11, 12, 13 and 14 .is provided with avapor dome, indicated in connection with still 1-1 bylnumeral 40. Fromthis dome a vapor line.41 extendsand is provided with two valvedbranches 42 and 43, one connecting with vapor line 38 and the other withvapor line 39.v Similar parts in stills 12, 13 and 14 are indicated bythe same numerals with the suiiixes a, bland c, respectively.

O n re;t'erring to Figures'l and'2, it will be noted that the vaporlines 39 from stills 12, 13 and 14,-.are connected-'by suitable lines 44with` the vapor linesr'38 fof stills 11, 12 and 13, respectively. I

From the header 37 lof; the exchanger in each still a condensate' line45 passes to the exterior of the still to any suitaiiile'fcoolingandre'ceivingdevices (not shown). j Still 15 is provided withl a vapordome 46, from ywhich a vapor line 47 connects with the line' 38, leadinginto the Ahea't exchanger. 'in' still14. 1' l In operating a vbattery ofstills of. the; character shown in .the'present drawings,-4 the' oil tobe treated, for example, Pennsylvania crude, is passed successivelythrough the stills, beginning withstill v11.. f desired temperaturegradient may be maintained between therstills, for example, 'with abattery of 5 stills as illustrated, the temperatured'itaference betweensuccessivefstills may-'bev vfrom 50 to 150 F. vAs is well knownl invther art, with continuous batteries" containing a greater number ofstills, alsmaller temperatureI gradient between stills is maintalned.

For purposes of illustration, in a battery such as that illustrated inthe drawings, the temperature maintained in still 11 may be about 350F., in still 12 about- 450 F.,fin

still 13 about 550o F., in still 141ab0ut 650 'F., and in still 15 about720 F. The steam linjected into the stills is varied `in accord- -ancewith the result desired in each still.

nlIt will be seen from the drawings that the vapors `from still 15, thelast fof the series, passdirectly into the tubular heat exchanger withinthe next precedin Astill 14. The vafromvvthe first still 11 may bepassed either intol thev exchangerin still 11 or may pass throughconnectlon 43 into the vapor discharge line 48, which likewise receivesthe vapors of the preceding stills passing out of the exchanger in still11.

In one mode of operation in accordance with the present invention, theconnections 42, 42, 42h and 42 arev closed. rIhe vapors from still 15then pass into the exchangerin still 14, wherein the are partiallycondensed. "I'he vapors rom still 14, together with thoseuncondensed inthe exchanger in that still pass through line 44 -into the exchanger instill 13, in which a further partial condensation takes place. Thevapors from still 13 Iand those uncondensed in the exchanger in still 13pass into the exchanger,

in still 12. Similarl the vapors formed in still 12, together Wit thosepassing through the exchanger in still 12,' enter the exchanger in still11. The vapors `from still 11 together with those uncondensed in theexchanger in still 11 pass through line 48 to any suitable condensingand receiving devices.4

In operating in the manner just described, the vapors from each stillare subjected to a controlled and moderate cooling action in theexchanger in the next preceding still, the

temperature gradient being suitably from 5,0 to 150 F., the same lasthat between the stills.. In this way a very clean fractionation ofthevapors may be secured. Light naphtha, steam and gas will, for example,issue from vapor line 48;" heavier naphtha will be condensed in theexchanger in still 11 y and will issue through discharge line 45;

refined oil will be condensed in the exchanger in still 12 and will bedischarged through line 45a; gas oil will be condensed in the 'exlglchanger in still 13 and .will issue through discharge line 45b andparaffin distillate will be condensed 4in the exchanger in still 14 and'the exchanger in the same still from' which theI are evolved,subsequently passing to the exc angersin the next preceding still.

In operating in this manner, the valves in the lines 43, 43, 43b and 43are closed and` those in the lines 42, 42a, 42b and 42c are opened. -Thevapors `:from still l5 then pass into the exchanger in still 14, and arejoined by the vapors from still 14, 4which enter the same exchangerthrough lines 4lc and 42.V Uncondensed vapors from the, exchangerinstill 14 pass'intothe exchanger instill 13, accompanied by vapors fromthe still 13. lSimilarly, uncondensed vapors from the exchanger-'instill 13 and vapors Yfrom the still 12 enter theexchanger in still 12and uncondensed vapors from the latter together with vapors'fromvstill11 enter the exchanger in still 11.4 Uncondensed vapors from theexchanger in Still 11 then ass out through the vapor line `48 to suitabdensers, Y`

In operating vin the' last described` manle conner it is apparent thatthe vapors .issuing t from each o f the stills in passing-,through theexchangers in-the same still, deposit any entrained oil that may becarried over, which is blended with condensate from'the vapors from thenext still in the case of still 14 and from the exchangerl in the nextstill in the cases of stills 11, 12 and 13. The desirabilit of this modeof operation, of course, depen s upon the character of roducts desiredand the nature of the oil being distilled.

We claim:

1. In apparatus for the distillation of oil, a still, a heatrexehangerwithin the still, means for conducting vapors from the exterior of the.vstill to the heat exchanger, means for conducting uncondensed vaporsfrom the heat exchanger to the exterior of the still, a dischar e linefor vapors evolved in the still and va ved means for connecting saiddischarge line with each of said conducting means.

2. In apparatusfor the distillation of oil, a series of stills, meansfor conducting oil successively. through said stills, heat exchangers inall of the stills except the laststill, means for conducting vaporsevolved in each still beyond the first still to the heat exchanger inthe preceding still, means for conducting vapors from each said heatexchangers except that in the first still to the means` for conductingvapors from each still except the last still to the heat exchanger inthe same still.

3. In apparatus for the distillation of oils a pluralit of stills, meansfor 'passing oil successive y vthrou h said stills, a heat exchanger ineach o said stills, a conduit for admitting vapors fromthe exterior ofeach still to the heat exchanger Within the still,

a conduit for discharging uncondensed vapors from the heat exchanger ineach still to the exterior of the still, a conduit for the discharge ofvapors evolved in each still, valve connections betweensaid lastmentioned conduit and each conduit connected with the heat exchanger inthe same still, and conduits connectin the discharge conduit-from' theheat exc anger of each still to the inlet conduit to the heat exchangerof the preceding still.

4. In a paratusfor a still, a E

the distillation of oil,

es extending in one direction of the still, headers for the reseotiveends of said tubes, conduits exten 'n from the exterior of the still toeach of said eat exchanger entirely within, thel still, said heatexchanger comprising a plu-` -rality of U-shapedtu headers, a vapor`outlet from the still, and va ved connections between said outlet andeach of said conduits.

5. The method of distilling oil which comprises passin oil successive ythrough a series of st' maintained at successively hi her temperatures,applying heat externa y of the still, passing the vapors formed in eachstill successively through heat exchangers in the preceding stills, thevapors.

'from each still admixing with the vapors from the succeeding stillentering the heat exchanger in the former still.

FRANK A. HOWARD. NATHANIEL E. LOOMIS.

